What's too late to have kids for a man?

First off, I want to establish that yes, technically it could be done at 80 years old lol.

I guess I'm just looking to get more opinions on what age ranges it goes from "Don't worry, you have time!" to "it's no longer a good idea"

Part of my reasoning is feeling like I could be robbing my children. If I'm hitting a helpless/elderly phase just as they're hitting their young adulthood, I know there are major downsides to that, and wouldn't want to get into that situation unless necessary.

Keep in mind, this is less of a "I'm X years old, is it too late for me?" And more of a general question of wanting to get peoples opinions on what age ranges it tends to go from
-you-have-time
to
-seriously-hurry-up
to
-you're-a-little-late-but-still-could